The question usually causes me to shake my head and take a deep breath before venturing forth into a response. I wish I could say that it is only posed by those with little to no training in the method; however, I've heard this from more than a few MDT-credentialed clinicians over the years.
Let's start with the foundation for a response: MDT is not a treatment. It is a way of thinking.
Examine the question from the context of the person asking it. It will help us understand why the question ever arises in the first place.
If you view the world of physical therapy (or musculoskeletal care as a whole) as just an assortment of treatment interventions - many being applied arbitrarily on an irrelevant patho-anatomical model - then it is easy to understand how MDT might not work. If you view MDT as "just another treatment intervention", and that treatment intervention isn't successful, then of course, you would ask "what do you do if MDT doesn't work?".
In that context, the question makes perfect sense. But it also professes a misunderstanding of what MDT really is in the first place.
MDT is a non-palpation-based system of assessment and treatment. The key word, the oft-forgotten word in fact, is "assessment". It is not a series of exercises applied arbitrarily to a patho-anatomical diagnosis. There is consistent clinical reasoning underlying its classification algorithm, with mutually exclusive categories and operational definitions. The clinically relevant treatment intervention generated is a logical byproduct of the system of assessment.
MDT is a way of thinking.
I always like to say that MDT always works - which always inspires the ire of many a clinician. I am reminded that there isn't a treatment that works for everyone. Well, you are right - there isn't a TREATMENT that works for everyone. The clinical reasoning and assessment process that are inherent to the approach does work for all patients. It provides a framework for the assessment of all musculoskeletal problems, be they spinal or extremity.
Sadly, if you don't fully comprehend the value of the MDT assessment process and what it provides for the patient and clinician, then you will always be looking for "something else" that is bigger or better to help "fix" the patient. There is a perception that surely there must be some "next great thing", some technique, some new "tool in the toolbox", that will lead you to the promised land. I could give you a list of 100 options. But simply maintaining a consistent line of clinical reasoning within the MDT framework will almost always provide sound answers, and they are oftentimes far more simple than perhaps many want to believe.
Before asking the question, stop and think about the patient's assessment and what it tells you about the mechanical loading capacity of the patient. Merge that with the patient's experiences and their responses to loading strategies. Listen. And guide. MDT has an answer, you just might not be asking the right questions along the way.
Photo credits: wadem